Explanation:
What's the closest galaxy to our Milky Way?
For many years astronomers thought it was the
Large Magellanic Cloud (LMC). But the
seemingly insignificant fuzzy patch shown above turned out to be part of a
galaxy that is even closer. Deemed the
"Sagittarius Dwarf",
this small galaxy went unnoticed until its discovery in 1994 by R. Ibata,
G. Gilmore and M. Irwin
(RGO).
The reason the Sagittarius Dwarf hadn't been discovered earlier is because
it is so dim, it is so spread out over the sky, and there are so many Milky
Way stars in front of it. The distance to the Sagittarius Dwarf was
recently measured to be about one third of the distance to the LMC.
Astronomers
now believe that this galaxy is slowly being torn apart by the
vast gravitational forces of our Galaxy.